guix system: Rename 'dmd-graph' to 'shepherd-graph'.

* doc/images/dmd-graph.dot: Rename to...
* doc/images/shepherd-graph.dot: ... this.
* doc.am (DOT_FILES): Adjust accordingly.
* guix/scripts/system.scm (dmd-service-node-label)
  (dmd-service-node-type, export-dmd-graph): Rename to...
  (shepherd-service-node-label, shepherd-service-node-type)
  (export-shepherd-graph): ... this.
  (show-help, process-action, process-command): Rename 'dmd-graph' to
  'shepherd-graph'.
* emacs/guix-command.el (guix-command-additional-execute-arguments)
  (guix-command-special-executors): Likewise.
* doc/guix.texi: Likewise.
* doc/emacs.texi (Emacs Popup Interface): Likewise.

emacs: Add interface for licenses.

* emacs/guix-main.scm (%license-param-alist): New variable.
  (license->sexp, find-licenses, license-entries): New procedures.
* emacs/guix-license.el (guix-license-get-entries)
  (guix-license-get-display, guix-license-insert-packages-button)
  (guix-license-insert-comment, guix-license-list-describe)
  (guix-license-list-show-packages): New procedures.
  (guix-licenses): New command.
* doc/emacs.texi (Emacs Licenses): New node.
  (Emacs Interface): Add it.
* doc/guix.texi (Top): Add it.
* NEWS: Mention new interface.

emacs: Add 'guix-packages-by-license' command.

* emacs/guix-main.scm (packages-by-license): New procedure.
(%patterns-makers): Add 'license' search type.
* emacs/guix-messages.el (guix-message-packages-by-license): New procedure.
(guix-messages): Use it.
* emacs/guix-ui-package.el (guix-packages-by-license): New command.
* doc/emacs.texi (Emacs Commands): Document it.

emacs: Buttonize licenses in "Package Info".

* emacs/guix-ui-package.el (guix-package-license): New button type.
  (guix-package-info-format, guix-output-info-format): Use it.
* doc/emacs.texi (Emacs Info buffer): Mention it.

Merge branch 'master' into core-updates

emacs: Add 'guix-search-by-name'.

* emacs/guix-ui-package.el (guix-search-by-name): New command.
* doc/emacs.texi (Emacs Commands): Document it.

emacs: Rename 'guix-search-by-name' to 'guix-packages-by-name'.

* emacs/guix-ui-package.el (guix-search-by-name): Rename to...
  (guix-packages-by-name): ... this.  Complete package name.
* doc/emacs.texi (Emacs Commands): Likewise.

emacs: Add interface for system generations.

* emacs/guix-main.scm (system-generation-boot-parameters)
(system-generation-param-alist, system-generation-sexps): New procedures.
(entries): Add 'system-generation' entry type.
* emacs/guix-messages.el (guix-result-message): Use the same messages
  for 'generation' and 'system-generation' entry types.
* emacs/guix-ui-system-generation.el: New file.
* emacs.am (ELFILES): Add it.
* doc/emacs.texi (Emacs Commands): Document new commands.
* NEWS: Mention new interface.

Merge branch 'master' into core-updates

emacs: Use "B" key in "Package List" to display latest builds.

* emacs/guix-ui-package.el (guix-package-list-latest-builds): New
  procedure.
  (guix-package-list-mode-map): Bind "B" key to it.
  (guix-output-list-mode-map): Likewise.
* doc/emacs.texi (Emacs List buffer): Document it.

emacs: Add Hydra interface.

* emacs/guix-utils.el (guix-hexify, guix-number->bool): New procedures.
  (guix-while-null): New macro.
* emacs/guix-hydra.el: New file.
* emacs/guix-hydra-build.el: New file.
* emacs/guix-hydra-jobset.el: New file.
* emacs.am (ELFILES): Add them.
* doc/emacs.texi (Emacs Hydra): New node.
  (Emacs Interface): Add it.
* doc/guix.texi (Top): Add it.
  (Substitutes): Mention Emacs interface.

emacs: Reorganize package/generation UI code.

Move the code for packages/generations interface from "guix-info.el",
"guix-list.el", "guix-base.el" and "guix.el" to "guix-ui-package.el" and
"guix-ui-generation.el".

* emacs/guix-base.el (guix-package-entry->name-specification)
  (guix-package-entries->name-specifications)
  (guix-package-id-and-output-by-output-id)
  (guix-package-installed-outputs, guix-process-package-actions)
  (guix-package-list-type, guix-package-info-type)
  (guix-continue-package-operation-p, guix-get-package-strings)
  (guix-insert-package-strings): Move to "guix-ui-package.el".
  (guix-generation-packages-buffer-name-function, guix-output-name-width)
  (guix-generation-packages-update-buffer, guix-generation-packages)
  (guix-generation-packages-buffer-name-default)
  (guix-generation-packages-buffer-name-long)
  (guix-generation-packages-buffer-name, guix-generation-packages-buffer)
  (guix-generation-insert-packages, guix-generation-insert-package)
  (guix-profile-generation-manifest-file, guix-delete-generations)
  (guix-profile-generation-packages-buffer, guix-switch-to-generation):
  Move to "guix-ui-generation.el".
* emacs/guix-info.el (guix-package-location, guix-package-name)
  (guix-package-source, guix-package-info-source)
  (guix-package-info-heading, guix-package-info-license)
  (guix-package-info-name, guix-package-info-name-button)
  (guix-package-info-version, guix-package-info-location)
  (guix-package-info-synopsis, guix-package-info-description)
  (guix-package-info-obsolete, guix-package-info-installed-outputs)
  (guix-package-info-uninstalled-outputs)
  (guix-package-info-insert-heading)
  (guix-package-info-define-insert-inputs)
  (guix-package-info-obsolete-string)
  (guix-package-info-insert-obsolete-text)
  (guix-package-info-insert-non-unique-text)
  (guix-package-info-insert-outputs, guix-package-info-insert-output)
  (guix-package-info-insert-action-button)
  (guix-package-info-auto-find-source)
  (guix-package-info-auto-download-source)
  (guix-package-info-download-buffer, guix-package-info-show-source)
  (guix-package-info-download-source, guix-package-info-insert-source)
  (guix-package-info-redisplay-after-download)
  (guix-output-info-insert-version, guix-output-info-insert-output):
  Move to "guix-ui-package.el".
  (guix-generation-info-number, guix-generation-info-current)
  (guix-generation-not-current, guix-generation-info-insert-number)
  (guix-generation-info-insert-current): Move to "guix-ui-generation.el".
* emacs/guix-list.el (guix-package-list-generation-marking-enabled)
  (guix-package-list-installed, guix-package-list-obsolete)
  (guix-package-list-get-name, guix-package-list-get-installed-outputs)
  (guix-package-list-marking-check, guix-package-list-mark-outputs)
  (guix-package-list-mark-install, guix-package-list-mark-delete)
  (guix-package-list-mark-upgrade, guix-package-list-mark-upgrades)
  (guix-list-mark-package-upgrades, guix-list-execute-package-actions)
  (guix-package-list-execute, guix-package-list-make-action)
  (guix-package-list-edit, guix-output-list-mark-install)
  (guix-output-list-mark-delete, guix-output-list-mark-upgrade)
  (guix-output-list-mark-upgrades, guix-output-list-make-action)
  (guix-output-list-describe, guix-output-list-edit): Move to
  "guix-ui-package.el".
  (guix-generation-list-get-current, guix-generation-list-switch)
  (guix-generation-list-generations-to-compare)
  (guix-generation-list-compare, guix-generation-list-show-packages)
  (guix-generation-list-show-added-packages)
  (guix-generation-list-show-removed-packages)
  (guix-generation-list-diff, guix-generation-list-diff-manifests)
  (guix-generation-list-ediff, guix-generation-list-ediff-manifests)
  (guix-generation-list-diff-packages)
  (guix-generation-list-ediff-packages)
  (guix-generation-list-mark-delete, guix-generation-list-execute): Move
  to "guix-ui-generation.el".
* emacs/guix.el: Remove.
  (guix, guix-faces, guix-edit): Move to "guix-base.el".
  (guix-list-single-package, guix-search-params, guix-search-history)
  (guix-get-show-packages, guix-search-by-name, guix-search-by-regexp)
  (guix-installed-packages, guix-obsolete-packages)
  (guix-all-available-packages, guix-newest-available-packages): Move
  to "guix-ui-package.el".
  (guix-get-show-generations, guix-generations, guix-last-generations)
  (guix-generations-by-time): Move to "guix-ui-generation.el".
* emacs.am (ELFILES): Remove "guix.el".  Add "guix-ui-package.el" and
  "guix-ui-generation.el".
* doc/emacs.texi (Emacs Appearance): Adjust accordingly.

emacs: Generalize buffer naming.

* emacs/guix-base.el (guix-buffer-name): New procedure.
  (guix-buffer-define-interface): Make ':buffer-name' a required keyword.
  (guix-update-after-operation, guix-buffer-name-function)
  (guix-buffer-name-simple, guix-buffer-name-default, guix-buffer-name)
  (guix-buffer-p, guix-buffers, guix-update-buffer)
  (guix-update-buffers-maybe-after-operation): Adjust, move and rename to...
* emacs/guix-ui.el (guix-ui-update-after-operation)
  (guix-ui-buffer-name-function, guix-ui-buffer-name-simple)
  (guix-ui-buffer-name-default, guix-ui-buffer-name)
  (guix-ui-buffer?, guix-ui-buffers, guix-ui-update-buffer)
  (guix-ui-update-buffers-after-operation): ... this.
  (guix-ui-define-interface): Generate
  'guix-ENTRY-TYPE-BUFFER-TYPE-buffer-name' procedure and pass it as
  ':buffer-name' argument.
  (guix-ui): New custom group.
* emacs/guix-info.el: Specify ':buffer-name' for the defined interfaces.
* emacs/guix-list.el: Likewise.
* doc/emacs.texi (Emacs Appearance): Adjust accordingly.

emacs: Split 'guix-root-map' keymap.

* emacs/guix-base.el: (guix-root-map): Split into...
  (guix-buffer-map): ... this and...
* emacs/guix-ui.el (guix-ui-map): ... this.
  (guix-ui-define-interface): Generate
  'guix-ENTRY-TYPE-BUFFER-TYPE-mode-map' keymaps inheriting them from
  'guix-ui-map' and 'guix-BUFFER-TYPE-mode-map'.
* emacs/guix-info.el (guix-info-mode-map): Use 'guix-buffer-map'.
* emacs/guix-list.el (guix-list-mode-map): Likewise.
* doc/emacs.texi (Emacs Keymaps): Document new keymaps.

emacs: Split 'guix-param-titles' variable.

Generate 'guix-ENTRY-TYPE-BUFFER-TYPE-titles' variables for each
ENTRY-TYPE and BUFFER-TYPE instead.

* emacs/guix-base.el (guix-param-titles): Remove.
  (guix-buffer-data): New variable.
  (guix-buffer-value, guix-buffer-param-title): New procedures.
  (guix-buffer-define-interface): Add ':titles' keyword.
* emacs/guix-info.el (guix-info-param-title): Adjust accordingly.
* emacs/guix-list.el (guix-list-param-title): Likewise.
  (guix-list-column-titles): Remove.
* doc/emacs.texi (Emacs Appearance): Adjust accordingly.

emacs: info: Split 'guix-info-format' variable.

* emacs/guix-info.el: Generate 'guix-ENTRY-TYPE-info-format' variables
  for 'package', 'installed-output', 'output' and 'generation' entry
  types.
  (guix-info-format): Remove.
  (guix-info-data): New variable.
  (guix-info-value): New procedure.
  (guix-info-define-interface): Add ':format' keyword.
* emacs/guix-base.el (guix-buffer-define-interface): Add ':reduced?'
  keyword.
* doc/emacs.texi (Emacs Appearance): Adjust accordingly.

emacs: info: Generalize inserting and formatting.

* emacs/guix-info.el: Use a more flexible format for inserting any data.
  (guix-info-ignore-empty-vals): Rename to...
  (guix-info-ignore-empty-values): ... this.
  (guix-info-insert-methods): Merge this and...
  (guix-info-displayed-params): ... this into...
  (guix-info-format): ... this.  Change format specifications.
  (guix-info-title-aliases, guix-info-value-aliases): New variables.
  (guix-info-displayed-params): Adjust for the new format.
  (guix-info-insert-entry): Likewise.
  (guix-package-info-fill-heading): Replace with...
  (guix-info-fill): ... this.
  (guix-info-insert-param): Replace with...
  (guix-info-insert-entry-unit): ... this.
  (guix-info-insert-title-default): Replace with...
  (guix-info-insert-title-format): ... this.
  (guix-info-insert-val-default): Replace with...
  (guix-info-insert-value-format): ... this.
  (guix-info-insert-val-simple): Replace with...
  (guix-info-insert-value-indent): ... this.
  (guix-package-info-insert-source): Adjust accordingly.
  (guix-package-info-insert-heading): Insert only name and version.
  (guix-package-info-define-insert-inputs): Do not generate
  'guix-package-info-insert-ENTRY-TYPE-inputs' procedures.
  (guix-info-fill-column, guix-info-insert-entry-default)
  (guix-info-method-funcall, guix-info-insert-file-path)
  (guix-info-insert-url, guix-info-insert-package-function)
  (guix-info-insert-installed-function)
  (guix-info-insert-output-function)
  (guix-info-insert-generation-function)
  (guix-package-info-heading-params)
  (guix-package-info-insert-with-heading)
  (guix-package-info-insert-description)
  (guix-package-info-insert-location)
  (guix-package-info-insert-full-names)
  (guix-package-info-insert-source-url): Remove.
  (guix-info-fill-column, guix-info-param-title)
  (guix-info-title-function, guix-info-value-function)
  (guix-info-title-method->function)
  (guix-info-value-method->function)
  (guix-info-insert-value-simple): New procedures.
* emacs/guix-utils.el (guix-buttonize, guix-button-type?): New
  procedures.
  (guix-split-string): Split multi-line strings and ignore empty lines.
* doc/emacs.texi (Emacs Appearance): Adjust accordingly.

emacs: list: Split 'guix-list-format' variable.

* emacs/guix-list.el: Generate 'guix-ENTRY-TYPE-list-format' variables
  for 'package', 'output' and 'generation' entry types.
  (guix-list-format): Remove.
  (guix-list-define-entry-type): Add ':format' keyword.
* doc/emacs.texi (Emacs Appearance): Adjust accordingly.

emacs: list: Configure format in one place.

* emacs/guix-list.el: (guix-list-column-format): Merge this and...
  (guix-list-column-value-methods): ... this into...
  (guix-list-format): ... this.  New variable.
  (guix-list-tabulated-vector): Adjust accordingly.
  (guix-list-tabulated-format): Likewise.
  (guix-list-tabulated-entry): Likewise.
* doc/emacs.texi (Emacs Appearance): Likewise.

Merge branch 'master' into core-updates